Analyst Horace Dediu says in a blog post that Apple’s iOS hardware ecosystem and related services is on schedule to have generated U.S.$1 trillion by 2018.

“In its first 10 years, the iPhone will have sold at least 1.2 billion units, making it the most successful product of all time," he writes. “The iPhone also enabled the iOS empire which includes the iPod touch, the iPad, the Apple Watch and Apple TV whose combined total unit sales will reach 1.75 billion units over 10 years. This total is likely to top 2 billion units by the end of 2018.”

The revenues from iOS product sales will reach $980 billion by middle of 2017, Dediu writes. In addition to hardware Apple also books iOS services revenues (including content) which have totaled more than $100 billion to date. This means that iOS will have generated over $1 trillion in revenues for Apple sometime this year, Dediu notes.